BACKGROUND
The body is made up of fat, lean tissue (muscles and organs), bones, water, and other substances. The amount and distribution of these materials gives a "typical" body contour at various ages.

For example, the body shape of a small child is different than that of an adult. In the same way, the young adult shape changes slightly to the body contours of an elderly person.

AGING CHANGES
Fat (adipose) tissue is increasingly deposited toward the center of the body, including around the abdominal organs. The adipose under the skin (subcutaneous fat) is decreased.

Lean body mass also decreases. The muscles, liver, kidney, and other organs lose some of their cells (atrophy). Bones lose some of their minerals and become less dense. Tissue atrophy decreases the amount of water in the body.

Height progressively decreases. The tendency to become shorter occurs among all races and both sexes. Height loss is related to aging changes in the bones, muscles, and joints.

The average height loss is 1 centimeter (about 0.4 inches) for every 10 years after age 40, and height loss is even greater after 70 years old. In total, aging may cause a loss of 1 to 3 inches in height.

Men often gain weight until about age 50, then begin to lose weight. Women usually gain weight until age 70, then begin to lose weight. Weight loss is, in part, caused by a loss of muscle tissue.

Some weight loss is caused by loss of subcutaneous fat stores. Part of the weight loss is caused by loss of bone tissue. Loss of body water also contributes to weight loss. If your appetite is poor (which is common among many older people), weight loss can be even more pronounced.

EFFECT OF CHANGES
Even healthy elderly people begin to appear bony, thin, and wasted, with a round belly and fragile arms and legs. Changes in fat and lean body mass cause an aged person to develop a heavier-appearing body and thin arms and legs.

The distance between the fingertips when the arms are held out to the sides (arm span) is the same as the (young adult) height. As you age, your arm span may be used as a measure of your "true" height, or it may be measured in comparison to your current height to determine height decrease.

COMMON PROBLEMS

• Because there is less body water, dehydration occurs readily.
• Doses of some medications may need to be adjusted because of changes in body water and fat.
• Changes in body shape contribute to problems with balance, mobility, and gait.

PREVENTION
Aging is a process of gradual deterioration in the body. Many age-related changes cannot be prevented. However, a lifestyle that includes exercise and a well-balanced diet will slow or minimize many problems related to aging.

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